Gesture based user interfaces allow users to control electronic devices and/or provide user input by hand gestures. Various systems have been described for identifying the hand gestures.
U.S. Pat. No. 4,988,981 to Zimmerman et al., titled: “Computer Data Entry and Manipulation Apparatus and Method”, describes a glove worn on a user's hand which is used in generating control signals for the manipulation of virtual objects.
U.S. Pat. No. 4,550,250 to Mueller et al., titled: “Cordless Digital Graphics Input Device”, describes a cordless graphics input device based on an infrared emitting module.
PCT publication WO2007/043036 to Zalevsky et al. describes identifying hand gestures using a coherent light source and a generator of a random speckle pattern.
Systems based on identifying hand gestures allow a wide range of inputs and can be used, for example, for text entry and for three dimensional control of animation in real time, such as in a virtual reality program running on a computer, as described in U.S. Pat. No. 6,452,584 to Walker et al., titled: “System for Data Management Based on Hand Gestures”.
Hand gestures may be used in simpler environments. US patent application publication 2008/0256494 to Greenfield describes using hand gestures to control the flow and temperature of water of a faucet. In one embodiment it is suggested that movements of the hand with one finger held up are interpreted as controlling the water flow, and movements with two fingers held up control the temperature.
U.S. Pat. No. 5,549,469 to Freeman et al., titled: “Hand Gesture Machine Control System”, describes a system in which hand gestures are used to move a hand icon over various controls on a screen. Only a single gesture is used to control multiple functions. An additional gesture is used to turn on the system and thus random gestures are prevented from being interpreted as control movements.
U.S. Pat. No. 7,821,541 to Delean, titled: “Remote Control Apparatus Using Gesture Recognition”, describes controlling a television system using hand gestures. Up and down movements are interpreted as controlling the volume, and left and right movements are interpreted as controlling the channel. In order to increase the number of commands that may be invoked via hand gestures, a sequence of multiple hand gestures can be interpreted as a single command. In order to avoid interpreting random movements as control instructions, a dormant mode is defined, and the user is required to signal a desire to move to an active mode before providing instructions.